1. Field of the Invention
The present invention generally relates to a biosensor chip and a method of sensing amount of cells, in particular with respect to a biosensor chip having precise count function and a sensing method.
2. Description of the Related Art
The purpose of cancer screening is aimed to detect cancer before the symptom is occurred. At present, the screening methods include medical imaging and indicator analysis of blood, urine . . . etc. Although medical imaging is of higher sensitivity towards cancer screening, it is still not suitable for detecting tumors of smaller than 0.1 cm (about 105 tumor cells). The conventional biomedical science indicators, such as prostate-specific antigen (PSA), cancer antigen 125 (CA-125), alpha-fetoprotein (AFP), human chorionic gonadotropin (HCG) and DR70, have been used as cancer marker on clinical detection; nonetheless, applying those detection methods to cancer screening still has various limitations, such as indirect determination on tumor cells counting, time-consuming blood sample separation or precision is interfered due to physical conditions (e.g. infection, inflammation or menstruation) and so on.
Currently, many biologists focus on research into cancer cells, but numerous tumor cells (and/or cancer stem cells) are characterized of un-differentiated, resulting that is hard to distinguish from the differences. Therefore, as far as the biologists are concerned, the dielectric property of cell is regarded as one of significant tools which can be applied to count amount of cells. The known methods, however, are invasive and time-consuming, and cells necessitate to be separated from the growth surface, took out of cell culture vessel and stained before counted. As a result, how to reach purposes of low cost, high quality, low power-consumption and being able to detect less biological molecules becomes a problem of development of biosensor.